Fast rejuvenation in bulk metallic glass induced by ultrasonic vibration precompression

Lou, Yan; Liu, Xiao; Yang, Xuan; Ge, Yanlin; Zhao, Dandan; Wang, Hao; Zhang, Lai-Chang; Liu, Zhiyuan

doi:10.1016/j.intermet.2019.106687

Cited by 25 publications

(10 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…To utilize the frictional heat, sliding speed and frequency need to be increased to improve efficiency of local energy supply. Ultrasonic vibration is the vibration beyond those audible to human ear, that is, at frequency greater than 20 kHz [11], under such high frequency, heat can build up readily [12]. Hence, many ultrasonic vibration relevant technologies have been developed and applied in various industrial processes, such as ultrasonic machining, ultrasonic welding, and ultrasonic forming [13,14].…”

Section: Introductionmentioning

confidence: 99%

Ultrasonic Assisted Sintering Using Heat Converted from Mechanical Energy

Liu

Zhao

et al. 2020

Metals

Self Cite

View full text Add to dashboard Cite

A new sintering method, namely ultrasonic assisted sintering (UAS), has been proposed using mechanical heat converted from high frequency motion between particles. Pure aluminum specimens with diameter of 5 mm and thickness of ~2 mm have been successfully sintered in two seconds. Based on the thermodynamic analysis, the underlying heating mechanism is quantitatively interpreted, which involves high-frequency interparticle friction and plastic deformation driven by ultrasonic squeezing. Consequently, temperature rises rapidly at a speed of about 300 K/s, and the maximum temperature reaches up to 0.9 times of melting point of the aluminum during UAS. The sintered specimens have a high density of dislocations, under the combined effects of dislocations and undulating stress field, volume diffusion coefficient for sintering increases by several orders of magnitude, therefore, rapid densification can be accomplished in seconds. In addition, the sintered aluminum has ultrahigh nanohardness (~1.13 GPa), which can be attributed to the hierarchical structure formed during UAS process.

show abstract

Section: Introductionmentioning

confidence: 99%

Ultrasonic Assisted Sintering Using Heat Converted from Mechanical Energy

Liu

Zhao

et al. 2020

Metals

Self Cite

View full text Add to dashboard Cite

show abstract

“…To specialized analyze the effects of the temperature rise and stress produced during the ultrasonic vibration on the rejuvenation properties of the amorphous alloys, we eliminate the effect of ultrasonic stress, and only the effect of temperature rise is studied separately. The temperature rise at different amplitudes is obtained according to previous research results [ 25 ]. That is, amplitudes of 19, 27, 36, and 43 μm correspond to temperature increases of 80, 150, 200, and 270 °C.…”

Section: Experimental Methodsmentioning

confidence: 99%

Rejuvenation of Zr-Based Bulk Metallic Glasses by Ultrasonic Vibration-Assisted Elastic Deformation

Lou

Liu

et al. 2020

Materials

Self Cite

View full text Add to dashboard Cite

The rejuvenation of Zr52.5Cu17.9Ni14.6Al10Ti5 bulk metallic glasses (BMGs) by ultrasonic vibration-assisted elastic deformation (UVEF) was studied herein. The UVEF-treated samples demonstrate an obvious rejuvenation and have a higher relaxation enthalpy and a smaller range of supercooled liquid regions than the as-cast samples. The fracture of the rejuvenated amorphous alloy is mainly ductile fracture, and shear deformation occurs in the deformation region. It is also found that as the amplitude increases, the free volume of the rejuvenated amorphous alloy increases, the yield strength and the elastic modulus decrease, and the formability increases. The free-volume content is used to characterize the degree of rejuvenation, and a mathematical model of the relationship between the ultrasonic amplitude and free volume is established. In addition, it is found that the ultrasonic vibration stress induces the additional free volume in the Zr-based bulk metallic glasses and improves the plasticizing behavior. The temperature rise caused by the ultrasonic thermal effect does not induce additional free volume.

show abstract

“…Employing a kind of cyclic loading, i.e. the ultrasonic vibration, Lou et al 31 found that the high frequency strain energy is converted into internal energy owing to heterogeneous atomic packing configuration of MGs. The MD simulation also shows that the structural rejuvenation increases effectively with the rise in the cyclic loading number and ultimately reached a saturated regime 32 .…”

Section: Introductionmentioning

confidence: 99%

Combined Effects of Annealing and Cyclic Loading on Structural Rejuvenation and Mechanical Properties of CuZr Metallic Glass: A Molecular Dynamics Study

Anggono¹,

Mahmoud

Suksatan

et al. 2022

Mat. Res.

View full text Add to dashboard Cite

Structural rejuvenation is one of the key topics in the field of metallic glasses (MGs). In this work, we evaluated the combined effects of annealing treatment and elastic cyclic loading to discover pathways for promoting structural rejuvenation and improving the mechanical properties in the MGs. Using molecular dynamics (MD) simulations, it was revealed that the sole cyclic loading led to the increase of rejuvenation degree; however, a saturated state was observed upon the 40 th cycle. On the other side, the sample exposed to the combined treatment exhibited a slight relaxation at the first step of cycling process and then a sharp rejuvenation degree was detected in the material. The thorough analyses indicated that the change in the fraction of coordination polyhedrons at the relaxation stage was the main reason for the extra rejuvenation in the sample exposed to the combined treatments. The results also suggest that the combination of rejuvenation treatments improves the magnitude of rejuvenation in the amorphous alloys. It should be noted that the increase of rejuvenation in the alloying systems accompanied with a reduction in the tensile strength and an enhancement in the homogenous plastic deformation.

show abstract

Fast rejuvenation in bulk metallic glass induced by ultrasonic vibration precompression

Cited by 25 publications

References 33 publications

Ultrasonic Assisted Sintering Using Heat Converted from Mechanical Energy

Ultrasonic Assisted Sintering Using Heat Converted from Mechanical Energy

Rejuvenation of Zr-Based Bulk Metallic Glasses by Ultrasonic Vibration-Assisted Elastic Deformation

Combined Effects of Annealing and Cyclic Loading on Structural Rejuvenation and Mechanical Properties of CuZr Metallic Glass: A Molecular Dynamics Study

Contact Info

Product

Resources

About